The present invention relates to a device for coating solid particles with a solidifying layer derived from a liquid, molten material. The device includes a turbine which rotates in a housing and comprises two disk parts. The solid particles are supplied on one surface of one disk part while the molten liquid material is supplied in a hollow space located between the two disk parts. The liquid flows through an annular gap between the disk parts and into an annular space in the housing that carries the solid particles which have been spun off to the outside, for the purpose of coating the solid particles.
A device of this type has been known, for example, from EP 0 048 312 A1. In this device, the two disk parts forming the turbine are in mutual axial contact by blade ribs extending from the upper disk part in a downward direction into the hollow space, and forming between them flow channels for the liquid, normally a melt, that is thereby guided into the annular gap. If the delivery quantity of the molten material is to be varied, for example for obtaining different droplet sizes in the coating veil, then the turbine must be removed and replaced by another turbine having a different size annular gap, or spacers must be provided that vary the spacing between the disk parts. In both cases it is necessary to remove the turbine from the housing.